Soil series profile
Oldsmar soil series
Oldsmar is a poorly drained soil with a sand surface, mapped on 323,359 acres in 26 counties in FL. Hydrologic group A/D.
- Drainage class
- Poorly drained 97% of mapped acres
- Hydrologic group
- A/D 92% of mapped acres
- Typical topsoil pH
- 5.3 strongly acidic · range 4.6–5.5
- Mapped area
- 323k acres in 26 counties, 1 state
Typical Oldsmar profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–6 in (A) | Sand | 5.3 | 3% | 96% | 1.5% |
| 6–38 in (E) | Sand | 5.3 | 2% | 96% | 0.25% |
| 38–50 in (Bh) | Sand | 4.9 | 8% | 90% | 3% |
| 50–80 in (Btg) | Sandy clay loam | 6.3 | 25% | 57% | 0.25% |

What this means
What Oldsmar soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Oldsmar soils is strongly acidic: pH 5.3 (most land between 4.6 and 5.5). Most vegetables and lawn grasses do best around 6.0 to 7.0, so lime is often needed; blueberries, azaleas and rhododendrons like it as it is.
Sandy topsoil covers 100% of mapped Oldsmar acres. It drains fast and warms early in spring, but dries out and loses nutrients quickly: mulch, compost and steady watering help. The most common surface texture is sand (65% of mapped Oldsmar acres).
100% of mapped Oldsmar acres is somewhat poorly to very poorly drained, so soil stays soggy for long spells after rain and in wet seasons. Raised beds, plants that tolerate wet feet, and not working the soil while wet all help.
For lawns and yards
On 100% of mapped acres, rain soaks in slowly (hydrologic groups C and D, including dual groups that are D until drained). Expect runoff and puddles after heavy rain: core-aerate compacted lawns and keep ground sloping away from foundations.
A seasonal high water table comes within 18 inches of the surface on 100% of mapped acres, often in spring. Basements, sump pumps and lawns in low spots feel it first.
For a septic system
For conventional septic absorption fields, NRCS rates 100% of the acres in mapped Oldsmar soils very limited, 0% somewhat limited and 0% not limited.
Where the soil is very limited (slow permeability, a high water table, flooding, shallow bedrock or steep slopes), alternative systems such as mound or sand-filter designs are common and cost more.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Oldsmar soil is found
Mapped acres
Oldsmar is mapped in Florida.
| County | Acres | Share of county land |
|---|---|---|
| Hendry County, FL | 77,899 | 10.4% |
| Charlotte County, FL | 45,831 | 10.3% |
| Collier County, FL | 35,230 | 4.7% |
| Lee County, FL | 31,087 | 6.1% |
| Glades County, FL | 22,709 | 4.6% |
| Martin County, FL | 19,264 | 5.5% |
| St. Lucie County, FL | 17,734 | 4.7% |
| Palm Beach County, FL | 15,168 | 1.2% |
| Indian River County, FL | 13,091 | 3.9% |
| Brevard County, FL | 10,005 | 1.2% |
| Highlands County, FL | 9,496 | 1.4% |
| Osceola County, FL | 8,545 | 1.0% |
| Polk County, FL | 7,810 | 0.7% |
| Sumter County, FL | 4,195 | 1.2% |
| DeSoto County, FL | 1,719 | 0.4% |
| Hillsborough County, FL | 1,476 | 0.2% |
| Flagler County, FL | 570 | 0.2% |
| Hardee County, FL | 399 | 0.1% |
| Seminole County, FL | 262 | 0.1% |
| Okeechobee County, FL | 219 | 0.0% |
| Sarasota County, FL | 172 | 0.0% |
| Manatee County, FL | 133 | 0.0% |
| Orange County, FL | 133 | 0.0% |
| Pasco County, FL | 99 | 0.0% |
| Citrus County, FL | 80 | 0.0% |
| St. Johns County, FL | 34 | 0.0% |
Septic absorption fields
NRCS rating, share of Oldsmar acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 100.0% |
Drainage, water table and flooding
Share of Oldsmar acres
- Depth to seasonal high water table
- About 1.0 feet (12 in) (median where reported); within 18 inches on 100% of acres.
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 1–1% (median 1%).
- Topsoil organic matter
- Median 1.5%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 0.0% |
| Moderately well drained | 0.0% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 97.4% |
| Very poorly drained | 2.6% |
Hydrologic soil group
Show as a table
| Category | Share of acres |
|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 0.0% |
| B: moderate infiltration | 0.0% |
| C: slow infiltration | 0.0% |
| D: very slow infiltration (clayey, shallow or wet) | 0.0% |
| A/D: D as is, A if drained | 91.8% |
| B/D: D as is, B if drained | 0.0% |
| C/D: D as is, C if drained | 8.2% |
Sources & data dates
- Source
- USDA NRCS Soil Survey Geographic Database (SSURGO), queried through Soil Data Access. Public domain.
- Data date
- SSURGO as published on November 3, 2026 (most recent survey area update October 26, 2026). NRCS refreshes SSURGO each October.
- Scope
- All map unit components named Oldsmar (component kind "Series") in SSURGO: 323,359 acres.
- Method
- Shares are by mapped acres of Oldsmar components. The profile comes from the single largest Oldsmar component. Full methodology.